render/pebble dash removal and brick cleaning

[mikeybowler]

Hi,

I'm in the process of removing old stained and blown pebble dash from my house and so far its coming off with very little effort and with very little if any damage to the bricks underneath All I'm left with is a slight sandy colour to the brick face due to the render mix used (not very good by the looks of it).

What is the best procedure/product/method of cleaning the bricks? So far I given a small area a treatment of 1:1 water:wickes brick acid and the results aren't brilliant (maybe i didnt leave it on long enough?)...Would using a jet washer be a bad idea? Would soaking the wall with a jet washer cause long term damp problems? is brick acid a bad idea?

Thanks Mike

 

[noseall]

Brick acid should not effect the (clay) bricks but it can leave unwanted stains.

Soaking the wall will make little difference to cement based products.

The concentration of retail mortar cleaner is rather weak and will ultimately neutralise once it has eaten through a half millimeter or so of cement based product. This results in many applications in order to remove anything thicker than smears.

By the way, are you aware that if you remove more than 24% of the total amount of render, that you are subject to building control regulations?

 

[mikeybowler]

Thanks for the advice. Can you recommend a brand of brick acid i should buy?

As for the 24%, i wasnt aware. To have more than 24% of a house rendered do you need to inform building control? What if the render was never a part of the original build?

Thanks.

 

[DIYWell]

If the pebble dash was the original spec, think carefully about leaving it uncovered. Often rendering, harling or pebble dash was used as the weather proofing layer on top of cheaper bricks.

 

[mikeybowler]

Speaking to my neighbor, who has lived in his house since it was build (50 years+) said that the house was pebble dashed in about 1979/1980. the majority of houses in the area don't have render/pebble dash on.

Does anyone know of a good brick cleaner they can recommend?

 

[mikeybowler]

Well the pebble dash is now removed and I'm about to clean the front and side of the house... Would sandblasting the brick be a bad idea to clean them up?

 

[hotrod]

Does anyone know of a good brick cleaner they can recommend?

I've just been cleaning up some brickwork using Sika concrete remover. It's working a treat. I've not diluted it, just damped the brickwork down, brushed it on, left it 10 mins than given it a quick scrub with an old stiff brush, and rinsed off with clean water. It's strong stuff....you need to be careful. Not sure you'll find in the DIY sheds. Maybe try a local merchant?

 

[DIYWell]

Well the pebble dash is now removed and I'm about to clean the front and side of the house... Would sandblasting the brick be a bad idea to clean them up?

Tricky one. Sandblasting can be agressive. The bricks may be fine, the mortar may not, or vice versa. I've seen a stone wall sandblasted and most was fine until it hit some softer stone and it cut at it like a blowtorch to a marshmallow.